CVE-2011-4520 in PROMOTIC
Summary
by MITRE
Heap-based buffer overflow in an ActiveX component in MICROSYS PROMOTIC before 8.1.5 allows remote attackers to cause a denial of service via a crafted web page.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 03/17/2025
The vulnerability identified as CVE-2011-4520 represents a critical heap-based buffer overflow within an ActiveX component embedded in MICROSYS PROMOTIC software versions prior to 8.1.5. This flaw exists within the component responsible for handling web page content and presents a significant security risk to systems running affected versions. The vulnerability specifically affects the ActiveX control implementation that processes user-supplied data from web pages, creating an environment where malicious actors can exploit the buffer overflow condition to execute arbitrary code or cause system instability.
The technical implementation of this vulnerability stems from inadequate input validation and memory management within the ActiveX component's data processing routines. When a web page containing crafted malicious data is loaded, the component fails to properly bounds-check incoming data before copying it into fixed-size heap buffers. This oversight allows attackers to write beyond the allocated buffer boundaries, potentially overwriting adjacent memory structures and corrupting program execution flow. The heap-based nature of the vulnerability means that the overflow occurs in dynamically allocated memory regions, making exploitation more complex but still highly effective for achieving denial of service conditions or code execution.
The operational impact of this vulnerability extends beyond simple denial of service scenarios to encompass potential system compromise and data integrity breaches. Remote attackers can leverage this flaw by constructing malicious web pages that trigger the vulnerable ActiveX component when loaded in Internet Explorer or other browsers that support ActiveX controls. The attack surface is particularly concerning as it requires no user interaction beyond visiting a malicious website, making it a prime target for drive-by download attacks. Systems running vulnerable versions of PROMOTIC software are at risk of complete system compromise, especially in industrial control environments where such software is commonly deployed for SCADA and process control applications.
Organizations should immediately implement mitigation strategies including updating to MICROSYS PROMOTIC version 8.1.5 or later, which contains the necessary patches to address the buffer overflow condition. Network segmentation and browser security hardening measures should be implemented to prevent users from accessing potentially malicious web content that could trigger this vulnerability. The vulnerability aligns with CWE-121 heap-based buffer overflow category and represents a significant risk under ATT&CK framework's TA0001 Initial Access and TA0005 Defense Evasion tactics. Security teams should also consider disabling ActiveX controls in web browsers where possible, as this reduces the attack surface for exploitation. Regular vulnerability assessments and penetration testing should be conducted to identify any remaining instances of the vulnerable software within the network infrastructure, particularly in industrial control systems where the risk of exploitation could have severe operational consequences.